<!DOCTYPE html>
<!-- Generated by pkgdown: do not edit by hand --><html lang="en"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta charset="utf-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><title>Convert units of distance or area — convert_units • EJAM</title><!-- favicons --><link rel="icon" type="image/png" sizes="16x16" href="../favicon-16x16.png"><link rel="icon" type="image/png" sizes="32x32" href="../favicon-32x32.png"><link rel="apple-touch-icon" type="image/png" sizes="180x180" href="../apple-touch-icon.png"><link rel="apple-touch-icon" type="image/png" sizes="120x120" href="../apple-touch-icon-120x120.png"><link rel="apple-touch-icon" type="image/png" sizes="76x76" href="../apple-touch-icon-76x76.png"><link rel="apple-touch-icon" type="image/png" sizes="60x60" href="../apple-touch-icon-60x60.png"><script src="../deps/jquery-3.6.0/jquery-3.6.0.min.js"></script><meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"><link href="../deps/bootstrap-5.3.1/bootstrap.min.css" rel="stylesheet"><script src="../deps/bootstrap-5.3.1/bootstrap.bundle.min.js"></script><link href="../deps/font-awesome-6.4.2/css/all.min.css" rel="stylesheet"><link href="../deps/font-awesome-6.4.2/css/v4-shims.min.css" rel="stylesheet"><script src="../deps/headroom-0.11.0/headroom.min.js"></script><script src="../deps/headroom-0.11.0/jQuery.headroom.min.js"></script><script src="../deps/bootstrap-toc-1.0.1/bootstrap-toc.min.js"></script><script src="../deps/clipboard.js-2.0.11/clipboard.min.js"></script><script src="../deps/search-1.0.0/autocomplete.jquery.min.js"></script><script src="../deps/search-1.0.0/fuse.min.js"></script><script src="../deps/search-1.0.0/mark.min.js"></script><!-- pkgdown --><script src="../pkgdown.js"></script><meta property="og:title" content="Convert units of distance or area — convert_units"><meta name="description" content="convert_units converts distance or area from specified units to other specified units."><meta property="og:description" content="convert_units converts distance or area from specified units to other specified units."><meta property="og:image" content="https://usepa.github.io/EJAM/logo.svg"></head><body>
    <a href="#main" class="visually-hidden-focusable">Skip to contents</a>


    <nav class="navbar navbar-expand-lg fixed-top bg-light" data-bs-theme="light" aria-label="Site navigation"><div class="container">

    <a class="navbar-brand me-2" href="../index.html">EJAM</a>

    <small class="nav-text text-warning me-auto" data-bs-toggle="tooltip" data-bs-placement="bottom" title="Released version">2.32.0</small>


    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbar" aria-controls="navbar" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>

    <div id="navbar" class="collapse navbar-collapse ms-3">
      <ul class="navbar-nav me-auto"><li class="active nav-item"><a class="nav-link" href="../reference/index.html">Reference</a></li>
<li class="nav-item dropdown">
  <button class="nav-link dropdown-toggle" type="button" id="dropdown-articles" data-bs-toggle="dropdown" aria-expanded="false" aria-haspopup="true">Articles</button>
  <ul class="dropdown-menu" aria-labelledby="dropdown-articles"><li><hr class="dropdown-divider"></li>
    <li><h6 class="dropdown-header" data-toc-skip>Overview for EJAM Users</h6></li>
    <li><a class="dropdown-item" href="../articles/0_whatis.html">What is EJAM</a></li>
    <li><a class="dropdown-item" href="../articles/0_webapp.html">Using EJAM</a></li>
    <li><hr class="dropdown-divider"></li>
    <li><h6 class="dropdown-header" data-toc-skip>For analysts using R</h6></li>
    <li><a class="dropdown-item" href="../articles/1_installing.html">Installing the EJAM R package</a></li>
    <li><a class="dropdown-item" href="../articles/2_quickstart.html">Quick Start Guide</a></li>
    <li><a class="dropdown-item" href="../articles/3_analyzing.html">Basics of Using EJAM for Analysis in RStudio</a></li>
    <li><a class="dropdown-item" href="../articles/4_advanced.html">Advanced Features</a></li>
  </ul></li>
<li class="nav-item"><a class="nav-link" href="../news/index.html">Changelog</a></li>
      </ul><ul class="navbar-nav"><li class="nav-item"><form class="form-inline" role="search">
 <input class="form-control" type="search" name="search-input" id="search-input" autocomplete="off" aria-label="Search site" placeholder="Search for" data-search-index="../search.json"></form></li>
<li class="nav-item"><a class="external-link nav-link" href="https://github.com/USEPA/EJAM/" aria-label="GitHub"><span class="fa fab fa-github fa-lg"></span></a></li>
      </ul></div>


  </div>
</nav><div class="container template-reference-topic">
<div class="row">
  <main id="main" class="col-md-9"><div class="page-header">
      <img src="../logo.svg" class="logo" alt=""><h1>Convert units of distance or area</h1>
      <small class="dont-index">Source: <a href="https://github.com/USEPA/EJAM/blob/HEAD/R/convert_units.R" class="external-link"><code>R/convert_units.R</code></a></small>
      <div class="d-none name"><code>convert_units.Rd</code></div>
    </div>

    <div class="ref-description section level2">
    <p><code>convert_units</code> converts distance or area from specified units to other specified units.</p>
    </div>

    <div class="section level2">
    <h2 id="ref-usage">Usage<a class="anchor" aria-label="anchor" href="#ref-usage"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">convert_units</span><span class="op">(</span><span class="va">x</span>, from <span class="op">=</span> <span class="st">"km"</span>, towhat <span class="op">=</span> <span class="st">"mi"</span><span class="op">)</span></span></code></pre></div>
    </div>

    <div class="section level2">
    <h2 id="arguments">Arguments<a class="anchor" aria-label="anchor" href="#arguments"></a></h2>


<dl><dt id="arg-x">x<a class="anchor" aria-label="anchor" href="#arg-x"></a></dt>
<dd><p>A number or vector of numbers to be converted.</p></dd>


<dt id="arg-from">from<a class="anchor" aria-label="anchor" href="#arg-from"></a></dt>
<dd><p>A string specifying original units of input parameter. Default is 'km' which is kilometers.
Note all must be in the same units.
Units can be specified as any of the following:
c(
'millimeter', 'millimeters', 'centimeter', 'centimeters', 'meter', 'meters', 'kilometer', 'kilometers',
"mm", "cm", "m", "km",
"sqmm", "sqcm", "sqm", "sqkm",
"mm2", "cm2", "m2", "km2",
'inch', 'inches', 'foot', 'feet', 'yard', 'yards', 'mile', 'miles',
"in", "ft", "yd", "mi",
"sqin", "sqft", "sqyd", "sqmi",
"in2", 'ft2', 'yd2', 'mi2'
)
Note that m2 is for square meters not square miles.</p></dd>


<dt id="arg-towhat">towhat<a class="anchor" aria-label="anchor" href="#arg-towhat"></a></dt>
<dd><p>A string specifying new units to convert to. Default is 'mi' which is miles.</p></dd>

</dl></div>
    <div class="section level2">
    <h2 id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
    <p>Returns a number or vector of numbers then length of the input x,
with each element corresponding to an input element converted to new units.</p>
    </div>
    <div class="section level2">
    <h2 id="details">Details<a class="anchor" aria-label="anchor" href="#details"></a></h2>
    <p>This function takes a number, or vector of numbers, representing distance/length or area
in one type of specified units, such as miles, and returns the corresponding number(s)
converted to some other units, such as kilometers. Units can be specified in various ways.
All inputs must be in the same units. All outputs must be in a single set of units as well.</p>
<p>NOTE: For some purposes, Census Bureau does this:</p>
<p>"The ANSI standard for converting square kilometers into square miles was used
( 1 square mile = 2.58998811 square kilometers)."
see <a href="https://www.census.gov/geo/reference/state-area.html" class="external-link">https://www.census.gov/geo/reference/state-area.html</a>
but the conversions in this function use 2.5899881034 not 2.58998811 sqkm/sqmi.
The difference is only 6.6 per billion (roughly 1 in 152 million), which is less than one tenth of a square kilometer out the entire USA.</p>
    </div>

    <div class="section level2">
    <h2 id="ref-examples">Examples<a class="anchor" aria-label="anchor" href="#ref-examples"></a></h2>
    <div class="sourceCode"><pre class="sourceCode r"><code><span><span class="fu">convert_units</span><span class="op">(</span><span class="fl">1</span>, <span class="st">'mi'</span>, <span class="st">'km'</span><span class="op">)</span></span>
<span><span class="fu">convert_units</span><span class="op">(</span><span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="fl">1e6</span>, <span class="fl">1</span><span class="op">)</span>, <span class="st">'sqm'</span>, <span class="st">'sqkm'</span><span class="op">)</span></span>
<span></span></code></pre></div>
    </div>
  </main><aside class="col-md-3"><nav id="toc" aria-label="Table of contents"><h2>On this page</h2>
    </nav></aside></div>


    <footer><div class="pkgdown-footer-left">
  <p>US EPA 2024</p>
</div>

<div class="pkgdown-footer-right">
  <p>EJAM Version 2.32.0</p>
</div>

    </footer></div>





  </body></html>

